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Abstract
Reproducibility is severely limited if instrument performance is assumed rather than measured. Within optical microscopy, instrument performance is typically measured using sub-resolution fluorescent beads. However, the process is performed infrequently as it is requires time and suitably trained staff to acquire and then process the bead images. Analysis software still requires the manual entry of imaging parameters. Human error from repeatedly typing these parameters can significantly affect the outcome of the analysis, rendering the results less reproducible. To avoid this issue, PyCalibrate has been developed to fully automate the analysis of bead images. PyCalibrate can be accessed either by executing the Python code locally or via a user-friendly web portal to further improve accessibility when moving between locations and machines. PyCalibrate interfaces with the BioFormats library to make it compatible with a wide range of proprietary image formats. In this study, PyCalibrate analysis performance is directly compared with alternative free-access analysis software PSFj, MetroloJ QC and DayBook 3 and is demonstrated to have equivalent performance but without the need for user supervision.
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Affiliation(s)
| | - Michele Gintoli
- Faculty of Science and Technology, University of Twente, 7500 AE Enschede, The Netherlands
| | - Alexander David Corbett
- Department of Physics and Astronomy, Stocker Road, Exeter, EX4 4QL, UK
- Living Systems Institute, University of Exeter, EX4 4QL, UK
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2
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Zou W, Kim H, Diffenderfer E, Carlson D, Koch C, Xiao Y, Teo B, Metz J, Maity A, Koumenis C, Cengel K, Dong L. FLASH OXYGEN DEPLETION EFFECTS DEPEND ON TISSUE VASCULATURE STRUCTURE: A SIMULATION STUDY ON SMALL ANIMAL PROTON FLASH EXPERIMENT. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01600-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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3
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Busch T, Velalopoulou A, Karagounis I, Cramer G, Skoufos G, Hatzigeorgiou A, Lanza M, Radaelli E, Assenmacher CA, Putt M, Kim M, Diffenderfer E, Dong L, Metz J, Koumenis C, Cengel K, Maity A. FLASH Mechanisms Track MECHANISMS OF FLASH RADIOTHERAPY SPARING OF NORMAL TISSUE AS INFORMED BY RNA-SEQ TRANSCRIPTOME ANALYSES. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01452-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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4
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Velalopoulou A, Karagounis I, Cramer G, Kim M, Skoufos G, Goia D, Hagan S, Verginadis I, Shoniyozov K, Chiango J, Cerullo M, Varner K, Yao L, Qin L, Hatzigeorgiou A, Minn A, Putt M, Lanza M, Assenmacher CA, Radaelli E, Huck J, Diffenderfer E, Dong L, Metz J, Koumenis C, Cengel K, Maity A, Busch T. FLASH Mechanisms Track (Oral Presentations) FLASH PROTON RADIOTHERAPY IS EQUIPOTENT TO STANDARD RADIATION IN TREATMENT OF MURINE SARCOMAS WHILE REDUCING TOXICITIES TO NORMAL SKIN, MUSCLE AND BONE. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01459-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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5
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Winter MJ, Pinion J, Tochwin A, Takesono A, Ball JS, Grabowski P, Metz J, Trznadel M, Tse K, Redfern WS, Hetheridge MJ, Goodfellow M, Randall AD, Tyler CR. Functional brain imaging in larval zebrafish for characterising the effects of seizurogenic compounds acting via a range of pharmacological mechanisms. Br J Pharmacol 2021; 178:2671-2689. [PMID: 33768524 DOI: 10.1111/bph.15458] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 02/17/2021] [Accepted: 03/14/2021] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND AND PURPOSE Functional brain imaging using genetically encoded Ca2+ sensors in larval zebrafish is being developed for studying seizures and epilepsy as a more ethical alternative to rodent models. Despite this, few data have been generated on pharmacological mechanisms of action other than GABAA antagonism. Assessing larval responsiveness across multiple mechanisms is vital to test the translational power of this approach, as well as assessing its validity for detecting unwanted drug-induced seizures and testing antiepileptic drug efficacy. EXPERIMENTAL APPROACH Using light-sheet imaging, we systematically analysed the responsiveness of 4 days post fertilisation (dpf; which are not considered protected under European animal experiment legislation) transgenic larval zebrafish to treatment with 57 compounds spanning more than 12 drug classes with a link to seizure generation in mammals, alongside eight compounds with no such link. KEY RESULTS We show 4dpf zebrafish are responsive to a wide range of mechanisms implicated in seizure generation, with cerebellar circuitry activated regardless of the initiating pharmacology. Analysis of functional connectivity revealed compounds targeting cholinergic and monoaminergic reuptake, in particular, showed phenotypic consistency broadly mapping onto what is known about neurotransmitter-specific circuitry in the larval zebrafish brain. Many seizure-associated compounds also exhibited altered whole brain functional connectivity compared with controls. CONCLUSIONS AND IMPLICATIONS This work represents a significant step forward in understanding the translational power of 4dpf larval zebrafish for use in neuropharmacological studies and for studying the events driving transition from small-scale pharmacological activation of local circuits, to the large network-wide abnormal synchronous activity associated with seizures.
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Affiliation(s)
- Matthew J Winter
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Joseph Pinion
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Anna Tochwin
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Aya Takesono
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Jonathan S Ball
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Piotr Grabowski
- Data Science and Artificial Intelligence, Clinical Pharmacology & Safety Sciences, AstraZeneca R&D, Cambridge, UK
| | - Jeremy Metz
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Maciej Trznadel
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Karen Tse
- Safety & Mechanistic Pharmacology, Clinical Pharmacology & Safety Sciences, AstraZeneca R&D, Cambridge, UK
- Sovereign House, GW Pharmaceuticals plc, Cambridge, UK
| | - Will S Redfern
- Safety & Mechanistic Pharmacology, Clinical Pharmacology & Safety Sciences, AstraZeneca R&D, Cambridge, UK
- Simcyp Division, Certara UK Limited, Sheffield, UK
| | - Malcolm J Hetheridge
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
| | - Marc Goodfellow
- Department of Mathematics & Living Systems Institute and EPSRC Centre for Predictive Modelling in Healthcare, University of Exeter, Exeter, Devon, UK
| | - Andrew D Randall
- University of Exeter Medical School, University of Exeter, Exeter, Devon, UK
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, Devon, UK
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6
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Goode O, Smith A, Łapińska U, Bamford R, Kahveci Z, Glover G, Attrill E, Carr A, Metz J, Pagliara S. Heterologous Protein Expression Favors the Formation of Protein Aggregates in Persister and Viable but Nonculturable Bacteria. ACS Infect Dis 2021; 7:1848-1858. [PMID: 34000805 DOI: 10.1021/acsinfecdis.1c00154] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Environmental and intracellular stresses can perturb protein homeostasis and trigger the formation and accumulation of protein aggregates. It has been recently suggested that the level of protein aggregates accumulated in bacteria correlates with the frequency of persister and viable but nonculturable cells that transiently survive treatment with multiple antibiotics. However, these findings have often been obtained employing fluorescent reporter strains. This enforced heterologous protein expression facilitates the visualization of protein aggregates but could also trigger the formation and accumulation of protein aggregates. Using microfluidics-based single-cell microscopy and a library of green fluorescent protein reporter strains, we show that heterologous protein expression favors the formation of protein aggregates. We found that persister and viable but nonculturable bacteria surviving treatment with antibiotics are more likely to contain protein aggregates and downregulate the expression of heterologous proteins. Our data also suggest that such aggregates are more basic with respect to the rest of the cell. These findings provide evidence for a strong link between heterologous protein expression, protein aggregation, intracellular pH, and phenotypic survival to antibiotics, suggesting that antibiotic treatments against persister and viable but nonculturable cells could be developed by modulating protein aggregation and pH regulation.
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Affiliation(s)
- Olivia Goode
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Ashley Smith
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Urszula Łapińska
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Rosemary Bamford
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Zehra Kahveci
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Georgina Glover
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Erin Attrill
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Alice Carr
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Jeremy Metz
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
| | - Stefano Pagliara
- Living Systems Institute and Biosciences, University of Exeter, Stocker Road, EX4 4QD, Exeter, United Kingdom
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7
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O'Keefe R, Lariviere M, Vachani C, Hampshire M, Bach C, Arnold-Korzeniowski K, Healy M, Metz J, Hill-Kayser C. FP09.04 Association Between Family History and Other Risk Factors for Lung Cancer: Analysis of an Internet-Based Risk Assessment. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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8
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Bonaterra GA, Bender K, Wilhelm B, Schwarzbach H, Metz S, Kelber O, Weiser D, Metz J, Kinscherf R. Effect of cholesterol re-supplementation and atorvastatin on plaque composition in the thoracic aorta of New Zealand white rabbits. BMC Cardiovasc Disord 2020; 20:420. [PMID: 32942987 PMCID: PMC7499881 DOI: 10.1186/s12872-020-01703-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/10/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Effects of re-supplementation of a cholesterol-enriched diet (CEDrs) on size, cholesterol content and morphology of already existing plaques are not known to date. METHODS A group of rabbits received standard chow (SC) for 6 weeks ("negative control"; for plasma lipid measurements only). Group I-IV received 2% CED (induction) for 6 weeks; thereafter, groups II-IV have been fed a SC (= cholesterol withdrawal) for 68 weeks. Afterwards, feeding of groups II-IV was continued as follows: Group II - 10 weeks SC, group III - 4 weeks 0.5% CED (~re-supplementation), afterwards 6 weeks SC (~withdrawal again); group IV - 4 weeks 0.5% CED (re-supplementation) + atorvastatin (2.5 mg/kg body weight/day), afterwards 6 weeks SC (~withdrawal again) + atorvastatin. Plasma lipids, but also plaque size, morphology and cholesterol contents of thoracic aortas were quantified. RESULTS After CEDrs, plasma cholesterol levels were increased. However, after withdrawal of CEDrs, plasma cholesterol levels decreased, whereas the cholesterol content of the thoracic aorta was increased in comparison with the group without CEDrs. Plaque size remained unaffected. Atorvastatin application did not change plasma cholesterol level, cholesterol content of the thoracic aorta and plaque size in comparison with the group without drug treatment. However, atorvastatin treatment increased the density of macrophages (MΦ) compared with the group without treatment, with a significant correlation between densities of MΦ (Mac-1+) and apoptotic (TUNEL+; TP53+), antigen-presenting (HLA-DR+) or oxidatively stressed (SOD2+) cells. CONCLUSIONS In rabbits with already existing plaques, CEDrs affects plaque morphology and cellular composition, but not plaque size. Despite missing effects on plasma cholesterol levels, cholesterol content of the thoracic aorta and size of already existing atherosclerotic plaques, atorvastatin treatment transforms the already existing lesions to a more active form, which may accelerate the remodelling to a more stable plaque.
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Affiliation(s)
- G A Bonaterra
- Department of Medical Cell Biology, University of Marburg, 35032, Marburg, Germany.
| | - K Bender
- Department of Anatomy and Cell Biology III, University of Heidelberg, 69120, Heidelberg, Germany
| | - B Wilhelm
- Department of Medical Cell Biology, University of Marburg, 35032, Marburg, Germany
| | - H Schwarzbach
- Department of Medical Cell Biology, University of Marburg, 35032, Marburg, Germany
| | - S Metz
- Department of Radiology, Technical University, 81675, Munich, Germany
| | - O Kelber
- Steigerwald Arzneimittelwerk, 64295, Darmstadt, Germany
| | - D Weiser
- Steigerwald Arzneimittelwerk, 64295, Darmstadt, Germany
| | - J Metz
- Department of Anatomy and Cell Biology III, University of Heidelberg, 69120, Heidelberg, Germany
| | - R Kinscherf
- Department of Medical Cell Biology, University of Marburg, 35032, Marburg, Germany
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9
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Cama J, Voliotis M, Metz J, Smith A, Iannucci J, Keyser UF, Tsaneva-Atanasova K, Pagliara S. Single-cell microfluidics facilitates the rapid quantification of antibiotic accumulation in Gram-negative bacteria. Lab Chip 2020; 20:2765-2775. [PMID: 32613221 PMCID: PMC7953842 DOI: 10.1039/d0lc00242a] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 06/15/2020] [Indexed: 06/01/2023]
Abstract
The double-membrane cell envelope of Gram-negative bacteria is a formidable barrier to intracellular antibiotic accumulation. A quantitative understanding of antibiotic transport in these cells is crucial for drug development, but this has proved elusive due to a dearth of suitable investigative techniques. Here we combine microfluidics and time-lapse auto-fluorescence microscopy to rapidly quantify antibiotic accumulation in hundreds of individual Escherichia coli cells. By serially manipulating the microfluidic environment, we demonstrated that stationary phase Escherichia coli, traditionally more refractory to antibiotics than growing cells, display reduced accumulation of the antibiotic ofloxacin compared to actively growing cells. Our novel microfluidic method facilitates the quantitative comparison of the role of the microenvironment versus that of the absence of key membrane transport pathways in cellular drug accumulation. Unlike traditional techniques, our assay is rapid, studying accumulation as the cells are dosed with the drug. This platform provides a powerful new tool for studying antibiotic accumulation in bacteria, which will be critical for the rational development of the next generation of antibiotics.
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Affiliation(s)
- Jehangir Cama
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- College of Engineering
, Mathematics and Physical Sciences
, University of Exeter
,
Exeter EX4 4QF
, UK
- Cavendish Laboratory
, Department of Physics
, University of Cambridge
,
JJ Thomson Avenue
, Cambridge CB3 0HE
, UK
| | - Margaritis Voliotis
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- College of Engineering
, Mathematics and Physical Sciences
, University of Exeter
,
Exeter EX4 4QF
, UK
| | - Jeremy Metz
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- School of Biosciences
, College of Life and Environmental Sciences
, University of Exeter
,
Exeter EX4 4QD
, UK
.
| | - Ashley Smith
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- School of Biosciences
, College of Life and Environmental Sciences
, University of Exeter
,
Exeter EX4 4QD
, UK
.
| | - Jari Iannucci
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- School of Biosciences
, College of Life and Environmental Sciences
, University of Exeter
,
Exeter EX4 4QD
, UK
.
| | - Ulrich F. Keyser
- Cavendish Laboratory
, Department of Physics
, University of Cambridge
,
JJ Thomson Avenue
, Cambridge CB3 0HE
, UK
| | - Krasimira Tsaneva-Atanasova
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- College of Engineering
, Mathematics and Physical Sciences
, University of Exeter
,
Exeter EX4 4QF
, UK
| | - Stefano Pagliara
- Living Systems Institute
, University of Exeter
,
Exeter EX4 4QD
, UK
.
- School of Biosciences
, College of Life and Environmental Sciences
, University of Exeter
,
Exeter EX4 4QD
, UK
.
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10
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Gironi B, Kahveci Z, McGill B, Lechner BD, Pagliara S, Metz J, Morresi A, Palombo F, Sassi P, Petrov PG. Effect of DMSO on the Mechanical and Structural Properties of Model and Biological Membranes. Biophys J 2020; 119:274-286. [PMID: 32610089 PMCID: PMC7376087 DOI: 10.1016/j.bpj.2020.05.037] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 04/08/2020] [Accepted: 05/22/2020] [Indexed: 12/23/2022] Open
Abstract
Dimethyl sulfoxide (DMSO) is widely used in a number of biological and biotechnological applications, mainly because of its effects on the cell plasma membrane, but the molecular origins of this action are yet to be fully clarified. In this work, we used two- and three-component synthetic membranes (liposomes) and the plasma membrane of human erythrocytes to investigate the effect of DMSO when added to the membrane-solvating environment. Fourier transform infrared spectroscopy and thermal fluctuation spectroscopy revealed significant differences in the response of the two types of liposome systems to DMSO in terms of the bilayer thermotropic behavior, available free volume of the bilayer, its excess surface area, and bending elasticity. DMSO also alters the mechanical properties of the erythrocyte membrane in a concentration-dependent manner and is capable of increasing membrane permeability to ATP at even relatively low concentrations (3% v/v and above). Taken in its entirety, these results show that DMSO is likely to have a differential effect on heterogeneous biological membranes, depending on their local composition and structure, and could affect membrane-hosted biological functions.
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Affiliation(s)
- Beatrice Gironi
- Dipartimento di Chimica Biologia e Biotecnologie, Università di Perugia, Perugia, Italy
| | - Zehra Kahveci
- Living Systems Institute and School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Beth McGill
- Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Bob-Dan Lechner
- Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Stefano Pagliara
- Living Systems Institute and School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Jeremy Metz
- Living Systems Institute and School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Assunta Morresi
- Dipartimento di Chimica Biologia e Biotecnologie, Università di Perugia, Perugia, Italy
| | - Francesca Palombo
- Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Paola Sassi
- Dipartimento di Chimica Biologia e Biotecnologie, Università di Perugia, Perugia, Italy.
| | - Peter G Petrov
- Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom.
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11
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White RR, Lin C, Leaves I, Castro IG, Metz J, Bateman BC, Botchway SW, Ward AD, Ashwin P, Sparkes I. Miro2 tethers the ER to mitochondria to promote mitochondrial fusion in tobacco leaf epidermal cells. Commun Biol 2020; 3:161. [PMID: 32246085 PMCID: PMC7125145 DOI: 10.1038/s42003-020-0872-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 02/25/2020] [Indexed: 12/19/2022] Open
Abstract
Mitochondria are highly pleomorphic, undergoing rounds of fission and fusion. Mitochondria are essential for energy conversion, with fusion favouring higher energy demand. Unlike fission, the molecular components involved in mitochondrial fusion in plants are unknown. Here, we show a role for the GTPase Miro2 in mitochondria interaction with the ER and its impacts on mitochondria fusion and motility. Mutations in AtMiro2's GTPase domain indicate that the active variant results in larger, fewer mitochondria which are attached more readily to the ER when compared with the inactive variant. These results are contrary to those in metazoans where Miro predominantly controls mitochondrial motility, with additional GTPases affecting fusion. Synthetically controlling mitochondrial fusion rates could fundamentally change plant physiology by altering the energy status of the cell. Furthermore, altering tethering to the ER could have profound effects on subcellular communication through altering the exchange required for pathogen defence.
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Affiliation(s)
| | - Congping Lin
- Department of Mathematics, Harrison Building, University of Exeter, Exeter, EX4 4QF, UK
- Center for Mathematical Sciences, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Lab of Engineering Modeling and Scientific Computing, Huazhong University of Science and Technology, Wuhan, China
| | - Ian Leaves
- Biosciences, CLES, Exeter University, Exeter, EX4 4QD, UK
| | - Inês G Castro
- Biosciences, CLES, Exeter University, Exeter, EX4 4QD, UK
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Jeremy Metz
- Biosciences, CLES, Exeter University, Exeter, EX4 4QD, UK
| | - Benji C Bateman
- Central Laser Facility, Science and Technology Facilities Council, Research Complex at Harwell, Didcot, Oxon, OX11 0FA, UK
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council, Research Complex at Harwell, Didcot, Oxon, OX11 0FA, UK
| | - Andrew D Ward
- Central Laser Facility, Science and Technology Facilities Council, Research Complex at Harwell, Didcot, Oxon, OX11 0FA, UK
| | - Peter Ashwin
- Department of Mathematics, Harrison Building, University of Exeter, Exeter, EX4 4QF, UK
| | - Imogen Sparkes
- Biosciences, CLES, Exeter University, Exeter, EX4 4QD, UK.
- School of Biological Sciences, University of Bristol, Bristol Life Sciences Building, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK.
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12
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Anagnostidis V, Sherlock B, Metz J, Mair P, Hollfelder F, Gielen F. Deep learning guided image-based droplet sorting for on-demand selection and analysis of single cells and 3D cell cultures. Lab Chip 2020; 20:889-900. [PMID: 31989120 DOI: 10.1039/d0lc00055h] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Uncovering the heterogeneity of cellular populations and multicellular constructs is a long-standing goal in fields ranging from antimicrobial resistance to cancer research. Emerging technology platforms such as droplet microfluidics hold the promise to decipher such heterogeneities at ultra-high-throughput. However, there is a lack of methods able to rapidly identify and isolate single cells or 3D cell cultures. Here we demonstrate that deep neural networks can accurately classify single droplet images in real-time based on the presence and number of micro-objects including single mammalian cells and multicellular spheroids. This approach also enables the identification of specific objects within mixtures of objects of different types and sizes. The training sets for the neural networks consisted of a few hundred images manually picked and augmented to up to thousands of images per training class. Training required less than 10 minutes using a single GPU, and yielded accuracies of over 90% for single mammalian cell identification. Crucially, the same model could be used to classify different types of objects such as polystyrene spheres, polyacrylamide beads and MCF-7 cells. We applied the developed method for the selection of 3D cell cultures generated with Hek293FT cells encapsulated in agarose gel beads, highlighting the potential of the technology for the selection of objects with a high diversity of visual appearances. The real-time sorting of single droplets was in-line with droplet generation and occurred at rates up to 40 per second independently of image size up to 480 × 480 pixels. The presented microfluidic device also enabled storage of sorted droplets to allow for downstream analyses.
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Affiliation(s)
| | - Benjamin Sherlock
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK.
| | - Jeremy Metz
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK.
| | - Philip Mair
- Department of Biochemistry, University of Cambridge, 80 Tennis Court, Cambridge, CB2 1QW, UK
| | - Florian Hollfelder
- Department of Biochemistry, University of Cambridge, 80 Tennis Court, Cambridge, CB2 1QW, UK
| | - Fabrice Gielen
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK.
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13
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Palumbo V, Tariq A, Borgal L, Metz J, Brancaccio M, Gatti M, Wakefield JG, Bonaccorsi S. Drosophila Morgana is an Hsp90-interacting protein with a direct role in microtubule polymerisation. J Cell Sci 2020; 133:jcs236786. [PMID: 31907206 PMCID: PMC6983718 DOI: 10.1242/jcs.236786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 12/17/2019] [Indexed: 12/25/2022] Open
Abstract
Morgana (Mora, also known as CHORD in flies) and its mammalian homologue, called CHORDC1 or CHP1, is a highly conserved cysteine and histidine-rich domain (CHORD)-containing protein that has been proposed to function as an Hsp90 co-chaperone. Morgana deregulation promotes carcinogenesis in both mice and humans while, in Drosophila, loss of mora causes lethality and a complex mitotic phenotype that is rescued by a human morgana transgene. Here, we show that Drosophila Mora localises to mitotic spindles and co-purifies with the Hsp90-R2TP-TTT supercomplex and with additional well-known Hsp90 co-chaperones. Acute inhibition of Mora function in the early embryo results in a dramatic reduction in centrosomal microtubule stability, leading to small spindles nucleated from mitotic chromatin. Purified Mora binds to microtubules directly and promotes microtubule polymerisation in vitro, suggesting that Mora directly regulates spindle dynamics independently of its Hsp90 co-chaperone role.
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Affiliation(s)
- Valeria Palumbo
- Dipartimento di Biologia e Biotecnologie Sapienza, Università di Roma, 00185 Rome, Italy
- Biosciences/Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Ammarah Tariq
- Biosciences/Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Lori Borgal
- Biosciences/Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Jeremy Metz
- Biosciences/Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Mara Brancaccio
- Dipartimento di Genetica, Biologia e Biochimica, Università di Torino, 10126 Torino, Italy
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie Sapienza, Università di Roma, 00185 Rome, Italy
- Istituto di Biologia e Patologia Molecolari del CNR, 00185 Rome, Italy
| | - James G Wakefield
- Biosciences/Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Silvia Bonaccorsi
- Dipartimento di Biologia e Biotecnologie Sapienza, Università di Roma, 00185 Rome, Italy
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14
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Mourabit S, Fitzgerald JA, Ellis RP, Takesono A, Porteus CS, Trznadel M, Metz J, Winter MJ, Kudoh T, Tyler CR. New insights into organ-specific oxidative stress mechanisms using a novel biosensor zebrafish. Environ Int 2019; 133:105138. [PMID: 31645010 DOI: 10.1016/j.envint.2019.105138] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/08/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Reactive oxygen species (ROS) arise as a result from, and are essential in, numerous cellular processes. ROS, however, are highly reactive and if left unneutralised by endogenous antioxidant systems, can result in extensive cellular damage and/or pathogenesis. In addition, exposure to a wide range of environmental stressors can also result in surplus ROS production leading to oxidative stress (OS) and downstream tissue toxicity. OBJECTIVES Our aim was to produce a stable transgenic zebrafish line, unrestricted by tissue-specific gene regulation, which was capable of providing a whole organismal, real-time read-out of tissue-specific OS following exposure to a wide range of OS-inducing environmental contaminants and conditions. This model could, therefore, serve as a sensitive and specific mechanistic in vivo biomarker for all environmental conditions that result in OS. METHODS To achieve this aim, we exploited the pivotal role of the electrophile response element (EpRE) as a globally-acting master regulator of the cellular response to OS. To test tissue specificity and quantitative capacity, we selected a range of chemical contaminants known to induce OS in specific organs or tissues, and assessed dose-responsiveness in each using microscopic measures of mCherry fluorescence intensity. RESULTS We produced the first stable transgenic zebrafish line Tg (3EpRE:hsp70:mCherry) with high sensitivity for the detection of cellular RedOx imbalances, in vivo in near-real time. We applied this new model to quantify OS after exposure to a range of environmental conditions with high resolution and provided quantification both of compound- and tissue-specific ROS-induced toxicity. DISCUSSION Our model has an extremely diverse range of potential applications not only for biomonitoring of toxicants in aqueous environments, but also in biomedicine for identifying ROS-mediated mechanisms involved in the progression of a number of important human diseases, including cancer.
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Affiliation(s)
- Sulayman Mourabit
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK.
| | | | - Robert P Ellis
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Aya Takesono
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Cosima S Porteus
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Maciej Trznadel
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Jeremy Metz
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Matthew J Winter
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Tetsuhiro Kudoh
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK.
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15
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Morrish RB, Hermes M, Metz J, Stone N, Pagliara S, Chahwan R, Palombo F. Single Cell Imaging of Nuclear Architecture Changes. Front Cell Dev Biol 2019; 7:141. [PMID: 31396512 PMCID: PMC6668442 DOI: 10.3389/fcell.2019.00141] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/10/2019] [Indexed: 12/31/2022] Open
Abstract
The dynamic architecture of chromatin, the macromolecular complex comprised primarily of DNA and histones, is vital for eukaryotic cell growth. Chemical and conformational changes to chromatin are important markers of functional and developmental processes in cells. However, chromatin architecture regulation has not yet been fully elucidated. Therefore, novel approaches to assessing chromatin changes at the single-cell level are required. Here we report the use of FTIR imaging and microfluidic cell-stretcher chips to assess changes to chromatin architecture and its effect on the mechanical properties of the nucleus in immune cells. FTIR imaging enables label-free chemical imaging with subcellular resolution. By optimizing the FTIR methodology and coupling it with cell segmentation analysis approach, we have identified key spectral changes corresponding to changes in DNA levels and chromatin conformation at the single cell level. By further manipulating live single cells using pressure-driven microfluidics, we found that chromatin decondensation – either during general transcriptional activation or during specific immune cell maturation – can ultimately lead to nuclear auxeticity which is a new biological phenomenon recently identified. Taken together our findings demonstrate the tight and, potentially bilateral, link between extra-cellular mechanotransduction and intra-cellular nuclear architecture.
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Affiliation(s)
- Rikke Brandstrup Morrish
- School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom.,Living Systems Institute and School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Michael Hermes
- School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Jeremy Metz
- Living Systems Institute and School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Nicholas Stone
- School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Stefano Pagliara
- Living Systems Institute and School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Richard Chahwan
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
| | - Francesca Palombo
- School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
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16
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Smith A, Metz J, Pagliara S. MMHelper: An automated framework for the analysis of microscopy images acquired with the mother machine. Sci Rep 2019; 9:10123. [PMID: 31300741 PMCID: PMC6626022 DOI: 10.1038/s41598-019-46567-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 06/26/2019] [Indexed: 11/23/2022] Open
Abstract
Live-cell imaging in microfluidic devices now allows the investigation of cellular heterogeneity within microbial populations. In particular, the mother machine technology developed by Wang et al. has been widely employed to investigate single-cell physiological parameters including gene expression, growth rate, mutagenesis, and response to antibiotics. One of the advantages of the mother machine technology is the ability to generate vast amounts of images; however, the time consuming analysis of these images constitutes a severe bottleneck. Here we overcome this limitation by introducing MMHelper ( https://doi.org/10.5281/zenodo.3254394 ), a publicly available custom software implemented in Python which allows the automated analysis of brightfield or phase contrast, and any associated fluorescence, images of bacteria confined in the mother machine. We show that cell data extracted via MMHelper from tens of thousands of individual cells imaged in brightfield are consistent with results obtained via semi-automated image analysis based on ImageJ. Furthermore, we benchmark our software capability in processing phase contrast images from other laboratories against other publicly available software. We demonstrate that MMHelper has over 90% detection efficiency for brightfield and phase contrast images and provides a new open-source platform for the extraction of single-bacterium data, including cell length, area, and fluorescence intensity.
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Affiliation(s)
- Ashley Smith
- Living Systems Institute, University of Exeter, Exeter, United Kingdom
- Biosciences, University of Exeter, Exeter, United Kingdom
| | - Jeremy Metz
- Living Systems Institute, University of Exeter, Exeter, United Kingdom.
- Biosciences, University of Exeter, Exeter, United Kingdom.
| | - Stefano Pagliara
- Living Systems Institute, University of Exeter, Exeter, United Kingdom.
- Biosciences, University of Exeter, Exeter, United Kingdom.
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17
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Wang Y, Metz J, Costello JL, Passmore J, Schrader M, Schultz C, Islinger M. Intracellular redistribution of neuronal peroxisomes in response to ACBD5 expression. PLoS One 2018; 13:e0209507. [PMID: 30589881 PMCID: PMC6307868 DOI: 10.1371/journal.pone.0209507] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/06/2018] [Indexed: 12/21/2022] Open
Abstract
Peroxisomes can be frequently found in proximity to other subcellular organelles such as the endoplasmic reticulum (ER), mitochondria or lysosomes. The tail-anchored protein ACBD5 was recently identified as part of a tethering complex at peroxisome-ER contact sites, interacting with the ER resident protein VAPB. Contact site disruption was found to significantly increase peroxisome motility, apparently interfering with intracellular positioning systems. Unlike other somatic cells, neurons have to distribute organelles across relatively long distances in order to maintain their extraordinary cellular polarity. Using confocal live imaging microscopy in cultured hippocampal neurons we observed that peroxisomes and mitochondria show a strikingly similar motility with approximately 10% performing microtubule-driven long range movements. In order to investigate if ER contacts influence overall peroxisome motility and cellular distribution patterns, hippocampal neurons were transfected with plasmids encoding ACBD5 to stimulate peroxisome-ER interactions. Overexpression of ACBD5 reduced peroxisomal long range movements in the neurites of the hippocampal cells by 70%, implying that ER attachment counteracts microtubule-driven peroxisome transport, while mitochondrial motility was unaffected. Moreover, the analyses of peroxisome distribution in fixed neurons unveiled a significant redistribution of peroxisomes towards the periphery of the perikaryon underneath the plasma membrane and into neurites, where peroxisomes are frequently found in close proximity to mitochondria. Surprisingly, further analysis of peroxisome and VAPB distribution upon ACBD5 expression did not reveal a substantial colocalization, implying this effect may be independent of VAPB. In line with these findings, expression of an ACBD5 variant unable to bind to VAPB still altered the localization of peroxisomes in the same way as the wild-type ACBD5. Thus, we conclude, that the VAPB-ACBD5 facilitated peroxisome-ER interaction is not responsible for the observed organelle redistribution in neurons. Rather, we suggest that additional ACBD5-binding proteins in neurons may tether peroxisomes to contact sites at or near the plasma membrane of neurons.
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Affiliation(s)
- Yunhong Wang
- Institute of Neuroanatomy, Center for Biomedicine & Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Jeremy Metz
- Biosciences, University of Exeter, Exeter, United Kingdom
| | | | | | | | - Christian Schultz
- Institute of Neuroanatomy, Center for Biomedicine & Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Markus Islinger
- Institute of Neuroanatomy, Center for Biomedicine & Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
- * E-mail:
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18
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Bokori-Brown M, Metz J, Petrov PG, Mussai F, De Santo C, Smart NJ, Saunders S, Knight B, Pastan I, Titball RW, Winlove CP. Interactions Between Pseudomonas Immunotoxins and the Plasma Membrane: Implications for CAT-8015 Immunotoxin Therapy. Front Oncol 2018; 8:553. [PMID: 30538953 PMCID: PMC6277520 DOI: 10.3389/fonc.2018.00553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 11/08/2018] [Indexed: 11/13/2022] Open
Abstract
Acute Lymphoblastic Leukemia (ALL) remains the most frequent cause of cancer-related mortality in children and novel therapies are needed for the treatment of relapsed/refractory childhood ALL. One approach is the targeting of ALL blasts with the Pseudomonas immunotoxin CAT-8015. Although CAT-8015 has potent anti-leukemia activity, with a 32% objective response rate in a phase 1 study of childhood ALL, haemolytic-uremic syndrome (HUS) and vascular leak syndrome (VLS), major dose-limiting toxicities, have limited the use of this therapeutic approach in children. Investigations into the pathogenesis of CAT-8015-induced HUS/VLS are hindered by the lack of an adequate model system that replicates clinical manifestations, but damage to vascular endothelial cells (ECs) and blood cells are believed to be major initiating factors in both syndromes. Since there is little evidence that murine models replicate human HUS/VLS, and CAT-8015-induced HUS/VLS predominantly affects children, we developed human models and used novel methodologies to investigate CAT-8015 interactions with red blood cells (RBCs) from pediatric ALL patients and ECs of excised human mesenteric arteries. We provide evidence that CAT-8015 directly interacts with RBCs, mediated by Pseudomonas toxin. We also show correlation between the electrical properties of the RBC membrane and RBC susceptibility to CAT-8015-induced lysis, which may have clinical implication. Finally, we provide evidence that CAT-8015 is directly cytototoxic to ECs of excised human mesenteric arteries. In conclusion, the human models we developed constitutes the first, and very important, step in understanding the origins of HUS/VLS in immunotoxin therapy and will allow further investigations of HUS/VLS pathogenesis.
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Affiliation(s)
- Monika Bokori-Brown
- College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Jeremy Metz
- College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Peter G. Petrov
- College of Engineering, Mathematics and Physical Sciences, Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Francis Mussai
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Carmela De Santo
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Neil J. Smart
- Exeter Surgical Health Services Research Unit, Royal Devon and Exeter Hospital, Exeter, United Kingdom
| | - Sarah Saunders
- Histopathology Department, Royal Devon and Exeter Hospital, Exeter, United Kingdom
| | - Bridget Knight
- National Institute for Health Research Exeter Clinical Research Facility, Royal Devon and Exeter National Health Service Foundation Trust, Exeter, United Kingdom
| | - Ira Pastan
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, United States
| | - Richard W. Titball
- College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - C. Peter Winlove
- College of Engineering, Mathematics and Physical Sciences, Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
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19
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Evans JP, Metz J, Anaspure R, Thomas WJ, King A, Goodwin VA, Smith CD. The spread of Injectate after ultrasound-guided lateral elbow injection - a cadaveric study. J Exp Orthop 2018; 5:27. [PMID: 30022381 PMCID: PMC6051955 DOI: 10.1186/s40634-018-0142-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 07/05/2018] [Indexed: 01/26/2023] Open
Abstract
Background Injections into the tendinous portion of the common extensor origin are a common intervention in the treatment of Lateral Elbow Tendinopathy (LET). Clinical trials report a heterogeneous selection of injectate volumes and delivery techniques, with systematic reviews finding no clear consensus. The aim of this study was to assess the intratendinous distribution and surrounding tissue contamination of ultrasound-guided injections into the Common Extensor Tendon (CET) of the elbow. Methods Twenty cadaveric elbows were injected by a Consultant Radiologist under Ultrasound guidance. Elbows were randomised to equal groups of 1 or 3 mls of methylene blue injection, delivered using single shot or fenestrated techniques. Following injection, each cadaver underwent a dry arthroscopy and dissection of superficial tissues. The CET was excised, set and divided into 1 mm sections using microtome. Each slice was photographed and analysed to assess spread and pixel density of injectate in four colour graduations. The cross-sectional area of distribution was calculated and compared between groups. Results In all 20 cadaveric samples, contamination of the joint was noted on arthroscopy and dissection. Injectate spread through over 97% of the cross-sectional area. No differences were found in intratendinous spread of injectate between differing volumes or techniques. Conclusion This study found that commonly used injection volumes and techniques distribute widely throughout cadaveric CETs. There was no improvement when the volume was increased from 1 to 3 mls or between single shot of fenestrated injection techniques. It should be noted that joint contamination using these techniques and volumes may be inevitable. Electronic supplementary material The online version of this article (10.1186/s40634-018-0142-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jonathan P Evans
- Royal Devon and Exeter NHS Foundation Trust, Exeter, UK. .,Wellcome Trust Biomedical Informatics Hub, University of Exeter, Exeter, UK. .,National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) South West Peninsula, University of Exeter Medical School, Exeter, UK. .,Health Services and Policy Research, Smeall Building, JS03, St Lukes Campus, Exeter, EX1 2LU, UK.
| | - Jeremy Metz
- Wellcome Trust Biomedical Informatics Hub, University of Exeter, Exeter, UK
| | | | | | - Andrew King
- Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Vicki A Goodwin
- National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) South West Peninsula, University of Exeter Medical School, Exeter, UK
| | - Chris D Smith
- Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
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20
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Mihailidis D, Ling C, Brady L, Scheuermann R, Kennedy C, Dong L, Metz J. PO-0993: Evaluation of MV imaging dose for the first clinical Halcyon system. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31303-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Mihailidis D, Scheuermann R, Kennedy C, Brady L, Dong L, Metz J. EP-2166: Halcyon clinical performance evaluation for Head and Neck treatments compared to Truebeam. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)32475-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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22
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Castro IG, Richards DM, Metz J, Costello JL, Passmore JB, Schrader TA, Gouveia A, Ribeiro D, Schrader M. A role for Mitochondrial Rho GTPase 1 (MIRO1) in motility and membrane dynamics of peroxisomes. Traffic 2018; 19:229-242. [PMID: 29364559 PMCID: PMC5888202 DOI: 10.1111/tra.12549] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/18/2018] [Accepted: 01/18/2018] [Indexed: 01/09/2023]
Abstract
Peroxisomes are dynamic organelles which fulfil essential roles in lipid and ROS metabolism. Peroxisome movement and positioning allows interaction with other organelles and is crucial for their cellular function. In mammalian cells, such movement is microtubule-dependent and mediated by kinesin and dynein motors. The mechanisms of motor recruitment to peroxisomes are largely unknown, as well as the role this plays in peroxisome membrane dynamics and proliferation. Here, using a combination of microscopy, live-cell imaging analysis and mathematical modelling, we identify a role for Mitochondrial Rho GTPase 1 (MIRO1) as an adaptor for microtubule-dependent peroxisome motility in mammalian cells. We show that MIRO1 is targeted to peroxisomes and alters their distribution and motility. Using a peroxisome-targeted MIRO1 fusion protein, we demonstrate that MIRO1-mediated pulling forces contribute to peroxisome membrane elongation and proliferation in cellular models of peroxisome disease. Our findings reveal a molecular mechanism for establishing peroxisome-motor protein associations in mammalian cells and provide new insights into peroxisome membrane dynamics in health and disease.
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Affiliation(s)
| | | | - Jeremy Metz
- Biosciences, University of Exeter, Exeter, UK
| | | | | | | | - Ana Gouveia
- Institute of Biomedicine, University of Aveiro, Aveiro, Portugal
| | - Daniela Ribeiro
- Institute of Biomedicine, University of Aveiro, Aveiro, Portugal
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23
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Bamford RA, Smith A, Metz J, Glover G, Titball RW, Pagliara S. Investigating the physiology of viable but non-culturable bacteria by microfluidics and time-lapse microscopy. BMC Biol 2017; 15:121. [PMID: 29262826 PMCID: PMC5738893 DOI: 10.1186/s12915-017-0465-4] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 11/30/2017] [Indexed: 11/29/2022] Open
Abstract
Background Clonal microbial populations often harbor rare phenotypic variants that are typically hidden within the majority of the remaining cells, but are crucial for the population’s resilience to external perturbations. Persister and viable but non-culturable (VBNC) cells are two important clonal bacterial subpopulations that can survive antibiotic treatment. Both persister and VBNC cells pose a serious threat to human health. However, unlike persister cells, which quickly resume growth following drug removal, VBNC cells can remain non-growing for prolonged periods of time, thus eluding detection via traditional microbiological assays. Therefore, understanding the molecular mechanisms underlying the formation of VBNC cells requires the characterization of the clonal population with single-cell resolution. A combination of microfluidics, time-lapse microscopy, and fluorescent reporter strains offers the perfect platform for investigating individual cells while manipulating their environment. Methods Here, we report a novel single-cell approach to investigate VBNC cells. We perform drug treatment, bacterial culturing, and live/dead staining in series by using transcriptional reporter strains and novel adaptations to the mother machine technology. Since we track each cell throughout the experiment, we are able to quantify the size, morphology and fluorescence that each VBNC cell displayed before, during and after drug treatment. Results We show that VBNC cells are not dead or dying cells but share similar phenotypic features with persister cells, suggesting a link between these two subpopulations, at least in the Escherichia coli strain under investigation. We strengthen this link by demonstrating that, before drug treatment, both persister and VBNC cells can be distinguished from the remainder of the population by their lower fluorescence when using a reporter strain for tnaC, encoding the leader peptide of the tnaCAB operon responsible for tryptophan metabolism. Conclusion Our data demonstrates the suitability of our approach for studying the physiology of non-growing cells in response to external perturbations. Our approach will allow the identification of novel biomarkers for the isolation of VBNC and persister cells and will open new opportunities to map the detailed biochemical makeup of these clonal subpopulations. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0465-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rosemary A Bamford
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Ashley Smith
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Jeremy Metz
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Georgina Glover
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | | | - Stefano Pagliara
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK. .,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK.
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24
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Winter MJ, Windell D, Metz J, Matthews P, Pinion J, Brown JT, Hetheridge MJ, Ball JS, Owen SF, Redfern WS, Moger J, Randall AD, Tyler CR. 4-dimensional functional profiling in the convulsant-treated larval zebrafish brain. Sci Rep 2017; 7:6581. [PMID: 28747660 PMCID: PMC5529444 DOI: 10.1038/s41598-017-06646-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 06/29/2017] [Indexed: 11/09/2022] Open
Abstract
Functional neuroimaging, using genetically-encoded Ca2+ sensors in larval zebrafish, offers a powerful combination of high spatiotemporal resolution and higher vertebrate relevance for quantitative neuropharmacological profiling. Here we use zebrafish larvae with pan-neuronal expression of GCaMP6s, combined with light sheet microscopy and a novel image processing pipeline, for the 4D profiling of chemoconvulsant action in multiple brain regions. In untreated larvae, regions associated with autonomic functionality, sensory processing and stress-responsiveness, consistently exhibited elevated spontaneous activity. The application of drugs targeting different convulsant mechanisms (4-Aminopyridine, Pentylenetetrazole, Pilocarpine and Strychnine) resulted in distinct spatiotemporal patterns of activity. These activity patterns showed some interesting parallels with what is known of the distribution of their respective molecular targets, but crucially also revealed system-wide neural circuit responses to stimulation or suppression. Drug concentration-response curves of neural activity were identified in a number of anatomically-defined zebrafish brain regions, and in vivo larval electrophysiology, also conducted in 4dpf larvae, provided additional measures of neural activity. Our quantification of network-wide chemoconvulsant drug activity in the whole zebrafish brain illustrates the power of this approach for neuropharmacological profiling in applications ranging from accelerating studies of drug safety and efficacy, to identifying pharmacologically-altered networks in zebrafish models of human neurological disorders.
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Affiliation(s)
- Matthew J Winter
- Biosciences, College of Life and Environmental Sciences, Exeter, Devon, EX4 4QD, United Kingdom.
| | - Dylan Windell
- Biosciences, College of Life and Environmental Sciences, Exeter, Devon, EX4 4QD, United Kingdom
| | - Jeremy Metz
- Biosciences, College of Life and Environmental Sciences, Exeter, Devon, EX4 4QD, United Kingdom
| | - Peter Matthews
- Medical School, University of Exeter, Exeter, Devon, EX4 4PS, United Kingdom
| | - Joe Pinion
- Medical School, University of Exeter, Exeter, Devon, EX4 4PS, United Kingdom
| | - Jonathan T Brown
- Medical School, University of Exeter, Exeter, Devon, EX4 4PS, United Kingdom
| | - Malcolm J Hetheridge
- Biosciences, College of Life and Environmental Sciences, Exeter, Devon, EX4 4QD, United Kingdom
| | - Jonathan S Ball
- Biosciences, College of Life and Environmental Sciences, Exeter, Devon, EX4 4QD, United Kingdom
| | - Stewart F Owen
- AstraZeneca, Global Compliance, Alderley Park, Macclesfield, Cheshire, SK10 4TF, United Kingdom
| | - Will S Redfern
- AstraZeneca R&D Innovative Medicines, Drug Safety & Metabolism, Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom
| | - Julian Moger
- Physics and Medical Imaging, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, Devon, EX4 4QL, United Kingdom
| | - Andrew D Randall
- Medical School, University of Exeter, Exeter, Devon, EX4 4PS, United Kingdom
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences, Exeter, Devon, EX4 4QD, United Kingdom
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25
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Chen JWC, Chen ZA, Rogala KB, Metz J, Deane CM, Rappsilber J, Wakefield JG. Cross-linking mass spectrometry identifies new interfaces of Augmin required to localise the γ-tubulin ring complex to the mitotic spindle. Biol Open 2017; 6:654-663. [PMID: 28351835 PMCID: PMC5450317 DOI: 10.1242/bio.022905] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The hetero-octameric protein complex, Augmin, recruits γ-Tubulin ring complex (γ-TuRC) to pre-existing microtubules (MTs) to generate branched MTs during mitosis, facilitating robust spindle assembly. However, despite a recent partial reconstitution of the human Augmin complex in vitro, the molecular basis of this recruitment remains unclear. Here, we used immuno-affinity purification of in vivo Augmin from Drosophila and cross-linking/mass spectrometry to identify distance restraints between residues within the eight Augmin subunits in the absence of any other structural information. The results allowed us to predict potential interfaces between Augmin and γ-TuRC. We tested these predictions biochemically and in the Drosophila embryo, demonstrating that specific regions of the Augmin subunits, Dgt3, Dgt5 and Dgt6 all directly bind the γ-TuRC protein, Dgp71WD, and are required for the accumulation of γ-TuRC, but not Augmin, to the mitotic spindle. This study therefore substantially increases our understanding of the molecular mechanisms underpinning MT-dependent MT nucleation. Summary: A map of subunit positional restrictions in Drosophila Augmin shows that Dgt3, Dgt5 and Dgt6 are all required to localise gamma-TuRC to mitotic spindles.
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Affiliation(s)
- Jack W C Chen
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Zhuo A Chen
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Kacper B Rogala
- Department of Statistics, University of Oxford, South Parks Road, Oxford OX1 3TG, UK
| | - Jeremy Metz
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Charlotte M Deane
- Department of Statistics, University of Oxford, South Parks Road, Oxford OX1 3TG, UK
| | - Juri Rappsilber
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Max Born Crescent, Edinburgh EH9 3BF, UK .,Chair of Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany
| | - James G Wakefield
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
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26
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Mihailidis D, Schuermann R, Kennedy C, Metz J. EP-1734: AAPM TG-119 benchmarking of a novel jawless dual level MLC collimation system. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)32097-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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27
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Barel O, Malicdan MCV, Ben-Zeev B, Kandel J, Pri-Chen H, Stephen J, Castro IG, Metz J, Atawa O, Moshkovitz S, Ganelin E, Barshack I, Polak-Charcon S, Nass D, Marek-Yagel D, Amariglio N, Shalva N, Vilboux T, Ferreira C, Pode-Shakked B, Heimer G, Hoffmann C, Yardeni T, Nissenkorn A, Avivi C, Eyal E, Kol N, Glick Saar E, Wallace DC, Gahl WA, Rechavi G, Schrader M, Eckmann DM, Anikster Y. Deleterious variants in TRAK1 disrupt mitochondrial movement and cause fatal encephalopathy. Brain 2017; 140:568-581. [PMID: 28364549 PMCID: PMC6075218 DOI: 10.1093/brain/awx002] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 11/22/2016] [Accepted: 12/05/2016] [Indexed: 01/12/2023] Open
Abstract
Cellular distribution and dynamics of mitochondria are regulated by several motor proteins and a microtubule network. In neurons, mitochondrial trafficking is crucial because of high energy needs and calcium ion buffering along axons to synapses during neurotransmission. The trafficking kinesin proteins (TRAKs) are well characterized for their role in lysosomal and mitochondrial trafficking in cells, especially neurons. Using whole exome sequencing, we identified homozygous truncating variants in TRAK1 (NM_001042646:c.287-2A > C), in six lethal encephalopathic patients from three unrelated families. The pathogenic variant results in aberrant splicing and significantly reduced gene expression at the RNA and protein levels. In comparison with normal cells, TRAK1-deficient fibroblasts showed irregular mitochondrial distribution, altered mitochondrial motility, reduced mitochondrial membrane potential, and diminished mitochondrial respiration. This study confirms the role of TRAK1 in mitochondrial dynamics and constitutes the first report of this gene in association with a severe neurodevelopmental disorder.
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Affiliation(s)
- Ortal Barel
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
| | - May Christine V Malicdan
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- NIH Undiagnosed Diseases Program, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Bruria Ben-Zeev
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Pediatric Neurology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
| | - Judith Kandel
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hadass Pri-Chen
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Joshi Stephen
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Inês G Castro
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Jeremy Metz
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Osama Atawa
- Palestenian Red Crescent Society Hospital, Department of Pediatrics, Hebron City, Palestine
| | - Sharon Moshkovitz
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
| | - Esther Ganelin
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Pediatric Neurology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
| | - Iris Barshack
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Department of Pathology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Sylvie Polak-Charcon
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Department of Pathology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Dvora Nass
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Department of Pathology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Dina Marek-Yagel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Metabolic Disease Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
| | - Ninette Amariglio
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
| | - Nechama Shalva
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Metabolic Disease Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
| | - Thierry Vilboux
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- Inova Translational Medicine Institute, Inova Health System, Falls Church, Virginia, USA
| | - Carlos Ferreira
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- Division of Genetics and Metabolism, Children’s National Health System, Washington DC, USA
| | - Ben Pode-Shakked
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Metabolic Disease Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
- The Dr. Pinchas Borenstein Talpiot Medical Leadership Program, Sheba Medical Center, Tel-Hashomer, Israel
| | - Gali Heimer
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Pediatric Neurology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
- The Dr. Pinchas Borenstein Talpiot Medical Leadership Program, Sheba Medical Center, Tel-Hashomer, Israel
| | - Chen Hoffmann
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Department of Radiology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Tal Yardeni
- Center for Mitochondrial and Epigenomic Medicine, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Andreea Nissenkorn
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Service for Rare Disorders, Pediatric Neurology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
| | - Camila Avivi
- Department of Pathology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Eran Eyal
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
| | - Nitzan Kol
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
| | - Efrat Glick Saar
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
| | - Douglas C Wallace
- Center for Mitochondrial and Epigenomic Medicine, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - William A Gahl
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- NIH Undiagnosed Diseases Program, NHGRI, National Institutes of Health, Bethesda, Maryland, USA
| | - Gideon Rechavi
- Sheba Cancer Research Center, Sheba Medical Center, Tel-Hashomer, Israel
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Michael Schrader
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - David M Eckmann
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yair Anikster
- The Wohl Institute for Translational Medicine, Sheba Medical Center, Tel-Hashomer, Israel
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Metabolic Disease Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Tel-Hashomer, Israel
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28
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Costello JL, Castro IG, Hacker C, Schrader TA, Metz J, Zeuschner D, Azadi AS, Godinho LF, Costina V, Findeisen P, Manner A, Islinger M, Schrader M. ACBD5 and VAPB mediate membrane associations between peroxisomes and the ER. J Cell Biol 2017; 216:331-342. [PMID: 28108524 PMCID: PMC5294785 DOI: 10.1083/jcb.201607055] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 10/31/2016] [Accepted: 12/22/2016] [Indexed: 01/20/2023] Open
Abstract
Costello et al. identify ACBD5 and VAPB as key components of a peroxisome–ER tether in mammalian cells. Disruption of this tethering complex leads to reduced peroxisomal membrane expansion and increased peroxisomal movement. Peroxisomes (POs) and the endoplasmic reticulum (ER) cooperate in cellular lipid metabolism and form tight structural associations, which were first observed in ultrastructural studies decades ago. PO–ER associations have been suggested to impact on a diverse number of physiological processes, including lipid metabolism, phospholipid exchange, metabolite transport, signaling, and PO biogenesis. Despite their fundamental importance to cell metabolism, the mechanisms by which regions of the ER become tethered to POs are unknown, in particular in mammalian cells. Here, we identify the PO membrane protein acyl-coenzyme A–binding domain protein 5 (ACBD5) as a binding partner for the resident ER protein vesicle-associated membrane protein-associated protein B (VAPB). We show that ACBD5–VAPB interaction regulates PO–ER associations. Moreover, we demonstrate that loss of PO–ER association perturbs PO membrane expansion and increases PO movement. Our findings reveal the first molecular mechanism for establishing PO–ER associations in mammalian cells and report a new function for ACBD5 in PO–ER tethering.
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Affiliation(s)
| | - Inês G Castro
- Biosciences, University of Exeter, Exeter EX4 4QD, England, UK
| | | | - Tina A Schrader
- Biosciences, University of Exeter, Exeter EX4 4QD, England, UK
| | - Jeremy Metz
- Biosciences, University of Exeter, Exeter EX4 4QD, England, UK
| | - Dagmar Zeuschner
- Max Planck Institute for Molecular Biomedicine, 48149 Muenster, Germany
| | - Afsoon S Azadi
- Biosciences, University of Exeter, Exeter EX4 4QD, England, UK
| | - Luis F Godinho
- Biosciences, University of Exeter, Exeter EX4 4QD, England, UK
| | - Victor Costina
- Institute for Clinical Chemistry, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Peter Findeisen
- Institute for Clinical Chemistry, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Andreas Manner
- Institute of Neuroanatomy, Center for Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Markus Islinger
- Institute of Neuroanatomy, Center for Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
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29
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Abstract
Organelle movement, distribution and interaction contribute to the organisation of the eukaryotic cell. Peroxisomes are multifunctional organelles which contribute to cellular lipid metabolism and ROS homeostasis. They distribute uniformly in mammalian cells and move along microtubules via kinesin and dynein motors. Their metabolic cooperation with mitochondria and the endoplasmic reticulum (ER) is essential for the β-oxidation of fatty acids and the synthesis of myelin lipids and polyunsaturated fatty acids. A key assay to assess peroxisome motility in mammalian cells is the expression of a fluorescent fusion protein with a peroxisomal targeting signal (e.g., GFP-PTS1), which targets the peroxisomal matrix and allows live-cell imaging of peroxisomes. Here, we first present a protocol for the transfection of cultured mammalian cells with the peroxisomal marker EGFP-SKL to observe peroxisomes in living cells. This approach has revealed different motile behaviour of peroxisomes and novel insight into peroxisomal membrane dynamics (Rapp et al., 1996; Wiemer et al., 1997; Schrader et al., 2000). We then present a protocol which combines the live-cell approach with peroxisome motility measurements and quantification of peroxisome dynamics in mammalian cells. More recently, we used this approach to demonstrate that peroxisome motility and displacement is increased when a molecular tether, which associates peroxisomes with the ER, is lost (Costello et al., 2017b). Silencing of the peroxisomal acyl-CoA binding domain protein ACBD5, which interacts with ER-localised VAPB, increased peroxisome movement in skin fibroblasts, indicating that membrane contact sites can modulate organelle distribution and motility. The protocols described can be adapted to other cell types and organelles to measure and quantify organelle movement under different experimental conditions.
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Affiliation(s)
- Jeremy Metz
- Biosciences, University of Exeter, Exeter, UK
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30
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Raju R, Abuzeid OM, Dada N, Kling M, Metz J, Frye IS. A Simple Innovative Technique for Managing Large Cystic Benign Adnexal Masses Using Single Port Laparoscopic Surgery. J Minim Invasive Gynecol 2016; 22:S129. [PMID: 27678695 DOI: 10.1016/j.jmig.2015.08.401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- R Raju
- Ob/Gyn, Hurley Medical Center, Flint, Michigan
| | - O M Abuzeid
- Ob/Gyn, Hurley Medical Center, Flint, Michigan
| | - N Dada
- Family Medicine, McLaren Regional Hospital, Flint, Michigan
| | - M Kling
- Ob/Gyn, McLaren Regional Medical Center, Flint, Michigan
| | - J Metz
- Ob/Gyn, McLaren Regional Medical Center, Flint, Michigan
| | - I S Frye
- Ob/Gyn, McLaren Regional Medical Center, Flint, Michigan
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31
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Green JM, Metz J, Lee O, Trznadel M, Takesono A, Brown AR, Owen SF, Kudoh T, Tyler CR. High-Content and Semi-Automated Quantification of Responses to Estrogenic Chemicals Using a Novel Translucent Transgenic Zebrafish. Environ Sci Technol 2016; 50:6536-45. [PMID: 27227508 DOI: 10.1021/acs.est.6b01243] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Rapid embryogenesis, together with genetic similarities with mammals, and the desire to reduce mammalian testing, are major incentives for using the zebrafish model in chemical screening and testing. Transgenic zebrafish, engineered for identifying target gene expression through expression of fluorophores, have considerable potential for both high-content and high-throughput testing of chemicals for endocrine activity. Here we generated an estrogen responsive transgenic zebrafish model in a pigment-free "Casper" phenotype, facilitating identification of target tissues and quantification of these responses in whole intact fish. Using the ERE-GFP-Casper model we show chemical type and concentration dependence for green fluorescent protein (GFP) induction and both spatial and temporal responses for different environmental estrogens tested. We also developed a semiautomated (ArrayScan) imaging and image analysis system that we applied to quantify whole body fluorescence responses for a range of different estrogenic chemicals in the new transgenic zebrafish model. The zebrafish model developed provides a sensitive and highly integrative system for identifying estrogenic chemicals, their target tissues and effect concentrations for exposures in real time and across different life stages. It thus has application for chemical screening to better direct health effects analysis of environmental estrogens and for investigating the functional roles of estrogens in vertebrates.
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Affiliation(s)
- Jon M Green
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - Jeremy Metz
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - Okhyun Lee
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - Maciej Trznadel
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - Aya Takesono
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - A Ross Brown
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - Stewart F Owen
- AstraZeneca, Global Environment , Alderley Park, Macclesfield, Cheshire SK10 4TF, United Kingdom
| | - Tetsuhiro Kudoh
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences, University of Exeter , Geoffrey Pope, Stocker Road, Exeter, Devon EX4 4QD, United Kingdom
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32
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Lin C, Schuster M, Guimaraes SC, Ashwin P, Schrader M, Metz J, Hacker C, Gurr SJ, Steinberg G. Active diffusion and microtubule-based transport oppose myosin forces to position organelles in cells. Nat Commun 2016; 7:11814. [PMID: 27251117 PMCID: PMC4895713 DOI: 10.1038/ncomms11814] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 05/03/2016] [Indexed: 11/26/2022] Open
Abstract
Even distribution of peroxisomes (POs) and lipid droplets (LDs) is critical to their role in lipid and reactive oxygen species homeostasis. How even distribution is achieved remains elusive, but diffusive motion and directed motility may play a role. Here we show that in the fungus Ustilago maydis ∼95% of POs and LDs undergo diffusive motions. These movements require ATP and involve bidirectional early endosome motility, indicating that microtubule-associated membrane trafficking enhances diffusion of organelles. When early endosome transport is abolished, POs and LDs drift slowly towards the growing cell end. This pole-ward drift is facilitated by anterograde delivery of secretory cargo to the cell tip by myosin-5. Modelling reveals that microtubule-based directed transport and active diffusion support distribution, mobility and mixing of POs. In mammalian COS-7 cells, microtubules and F-actin also counteract each other to distribute POs. This highlights the importance of opposing cytoskeletal forces in organelle positioning in eukaryotes. The mechanisms underlying the positioning of eukaryotic organelles remain elusive. Here Lin et al. use imaging and a mathematical model to show that microtubule-based transport and active diffusion and actin-based polar drift act together to facilitate even distribution of peroxisomes in filamentous fungi.
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Affiliation(s)
- Congping Lin
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.,Mathematics, University of Exeter, North Park Road, Exeter EX4 4QF, UK
| | - Martin Schuster
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | | | - Peter Ashwin
- Mathematics, University of Exeter, North Park Road, Exeter EX4 4QF, UK
| | - Michael Schrader
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Jeremy Metz
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Christian Hacker
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Sarah Jane Gurr
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Gero Steinberg
- School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
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33
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Gao H, Metz J, Teanby NA, Ward AD, Botchway SW, Coles B, Pollard MR, Sparkes I. In Vivo Quantification of Peroxisome Tethering to Chloroplasts in Tobacco Epidermal Cells Using Optical Tweezers. Plant Physiol 2016; 170:263-72. [PMID: 26518344 PMCID: PMC4704594 DOI: 10.1104/pp.15.01529] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 10/24/2015] [Indexed: 05/19/2023]
Abstract
Peroxisomes are highly motile organelles that display a range of motions within a short time frame. In static snapshots, they can be juxtaposed to chloroplasts, which has led to the hypothesis that they are physically interacting. Here, using optical tweezers, we tested the dynamic physical interaction in vivo. Using near-infrared optical tweezers combined with TIRF microscopy, we were able to trap peroxisomes and approximate the forces involved in chloroplast association in vivo in tobacco (Nicotiana tabacum) and observed weaker tethering to additional unknown structures within the cell. We show that chloroplasts and peroxisomes are physically tethered through peroxules, a poorly described structure in plant cells. We suggest that peroxules have a novel role in maintaining peroxisome-organelle interactions in the dynamic environment. This could be important for fatty acid mobilization and photorespiration through the interaction with oil bodies and chloroplasts, highlighting a fundamentally important role for organelle interactions for essential biochemistry and physiological processes.
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Affiliation(s)
- Hongbo Gao
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Jeremy Metz
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Nick A Teanby
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Andy D Ward
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Stanley W Botchway
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Benjamin Coles
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Mark R Pollard
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
| | - Imogen Sparkes
- Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom (H.G., J.M., I.S.);School of Earth Sciences, University of Bristol, Clifton, Bristol BS8 1RJ, United Kingdom (N.A.T.); andCentral Laser Facility, Science and Technology Facilities Council, Didcot, Oxon OX11 0FA, United Kingdom (A.D.W., S.W.B., B.C., M.R.P.)
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Kenton O, Dachi J, Metz J, Avery S. SU-E-E-03: Developing Solutions to Critical Radiation Oncology Challenges in Tanzania. Med Phys 2014. [DOI: 10.1118/1.4887934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Hayward D, Metz J, Pellacani C, Wakefield JG. Synergy between multiple microtubule-generating pathways confers robustness to centrosome-driven mitotic spindle formation. Dev Cell 2014; 28:81-93. [PMID: 24389063 PMCID: PMC3898610 DOI: 10.1016/j.devcel.2013.12.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 10/21/2013] [Accepted: 12/03/2013] [Indexed: 12/30/2022]
Abstract
The mitotic spindle is defined by its organized, bipolar mass of microtubules, which drive chromosome alignment and segregation. Although different cells have been shown to use different molecular pathways to generate the microtubules required for spindle formation, how these pathways are coordinated within a single cell is poorly understood. We have tested the limits within which the Drosophila embryonic spindle forms, disrupting the inherent temporal control that overlays mitotic microtubule generation, interfering with the molecular mechanism that generates new microtubules from preexisting ones, and disrupting the spatial relationship between microtubule nucleation and the usually dominant centrosome. Our work uncovers the possible routes to spindle formation in embryos and establishes the central role of Augmin in all microtubule-generating pathways. It also demonstrates that the contributions of each pathway to spindle formation are integrated, highlighting the remarkable flexibility with which cells can respond to perturbations that limit their capacity to generate microtubules.
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Affiliation(s)
- Daniel Hayward
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Jeremy Metz
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Claudia Pellacani
- Istituto Pasteur-Fondazione Cenci Bolognetti, "La Sapienza" Università di Roma, P.le A. Moro 5, 00185 Roma, Italy
| | - James G Wakefield
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.
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Ding X, Kassaee A, Avery S, Metz J, Lichtenwalner P, Huang L, Butterwick I. SU-E-T-724: Evaluate the Impact of Bowel Gas Movement in Pancreatic Proton Therapy. Med Phys 2013. [DOI: 10.1118/1.4815151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Ding X, Avery S, Kassaee A, Metz J, Prionas V, Huang L, McQuiggan S, Butterwick I, Martinsen A. SU-E-T-684: A Comprehensive Dosimetric Study of Pancreatic Cancer Treatment Using Three Dimensional (3D) Conformal Radiation Therapy, Intensity-Modulated Radiation Therapy (IMRT), Volumetric Modulated Radiation Therapy (VMAT), Passive Scattering and Modul. Med Phys 2013. [DOI: 10.1118/1.4815111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Dolney D, McDonough J, Vapiwala N, Metz J. SU-E-CAMPUS-T-06: Dose Perturbations by Electromagnetic Transponders in the Proton Environment. Med Phys 2013. [DOI: 10.1118/1.4815190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Mukherjee S, Diaz Valencia JD, Stewman S, Metz J, Monnier S, Rath U, Asenjo AB, Charafeddine RA, Sosa HJ, Ross JL, Ma A, Sharp DJ. Human Fidgetin is a microtubule severing the enzyme and minus-end depolymerase that regulates mitosis. Cell Cycle 2012; 11:2359-66. [PMID: 22672901 DOI: 10.4161/cc.20849] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Fidgetin is a member of the AAA protein superfamily with important roles in mammalian development. Here we show that human Fidgetin is a potent microtubule severing and depolymerizing the enzyme used to regulate mitotic spindle architecture, dynamics and anaphase A. In vitro, recombinant human Fidgetin severs taxol-stabilized microtubules along their length and promotes depolymerization, primarily from their minus-ends. In cells, human Fidgetin targets to centrosomes, and its depletion with siRNA significantly reduces the velocity of poleward tubulin flux and anaphase A chromatid-to-pole motion. In addition, the loss of Fidgetin induces a microtubule-dependent enlargement of mitotic centrosomes and an increase in the number and length of astral microtubules. Based on these data, we propose that human Fidgetin actively suppresses microtubule growth from and attachment to centrosomes.
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Affiliation(s)
- Suranjana Mukherjee
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY, USA
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Betancourt R, Plastaras J, Metz J, Kassaee A. Investigation Of Calypso 4D As A Respiratory Gating System For EBRT For Pancreatic Cancer By Correlating The Pancreatic Movement Using Calypso 4D With The Relative Breathing Motion Obtained By Anzai Motion Monitoring System. Int J Radiat Oncol Biol Phys 2011. [DOI: 10.1016/j.ijrobp.2011.06.1374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Metz J, Edelstein T, Divaris M, Zail SS. Effect of Total Dose Infusion of Iron-dextran on Iron, Folate, and Vitamin B12 Nutrition in Postpartum Anaemia. Br Med J 2011; 3:403-6. [PMID: 20791302 DOI: 10.1136/bmj.3.5562.403] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Thukral A, Metz J, Hwang WT, O'Dwyer P, Plastaras J, Both S, Bar-Ad V, Ad VB. Toxicity data for preoperative concurrent chemoradiotherapy with oxaliplatin and continuous infusion 5-fluorouracil for locally advanced esophageal cancer. Dis Esophagus 2011; 24:330-6. [PMID: 21143694 DOI: 10.1111/j.1442-2050.2010.01145.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The purpose of this retrospective analysis was to characterize the feasibility and tolerability of oxaliplatin/5-fluorouracil (5-FU) given concurrently with radiotherapy for patients with locally advanced esophageal cancer. Between July 2005 and March 2009, 15 patients with clinical stage T3/T4 and/or N1/M1a lower esophageal or gastroesophageal junction adenocarcinoma were treated with preoperative chemoradiotherapy using oxaliplatin every 2 weeks and continuous infusion 5-FU. The main treatment-related toxicities were oral mucositis and dysphagia. During the first 2 weeks of treatment, 20% of patients presented with grade 1-2 oral mucositis, and one patient developed grade 1 dysphagia. In weeks 3-4, 53% of the patients experienced grade 1-2 mucositis, and 40% experienced grade 1-2 dysphagia. One patient only experienced grade 3 mucositis in week 4. Three patients (20%) had grade 3-4 dysphagia in weeks 3-4 and were continued on intravenous fluids and pain medications. During the last 2 weeks of chemoradiotherapy, 53% of patients reported grade 1-2 oral mucositis, mostly grade 1 and 73% of patients experienced grade 1-2 dysphagia and 26% patients experienced grade 3-4 dysphagia. Other toxicities included fatigue, nausea, neuropathy, and diarrhea. Only one patient experienced > 10% weight loss. The whole group was treated with aggressive supportive care during radiotherapy. Five (33%) patients achieved a pathological complete response. No patients developed locoregional failure. Sixty percent of the patients developed distant metastases and the 2-year disease-free survival was 53%. The median survival was 3.2 years with the 2-year overall survival of 73%. Preoperative oxaliplatin/5-FU-based chemoradiotherapy for locally advanced esophageal cancer is feasible, but associated with substantial gastrointestinal toxicity. A careful attention to nutrition and hydration throughout the course of therapy is required.
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Affiliation(s)
- A Thukral
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
| | - J Metz
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
| | - W-T Hwang
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
| | - P O'Dwyer
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
| | - J Plastaras
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
| | - S Both
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
| | - V Bar-Ad
- Department of Radiation OncologyDepartment of Biostatistics and EpidemiologyDepartment of Hematology-Oncology, University of Pennsylvania, Philadelphia, USA
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Bonaterra GA, Heinrich EU, Kelber O, Weiser D, Metz J, Kinscherf R. Anti-inflammatory effects of the willow bark extract STW 33-I (Proaktiv(®)) in LPS-activated human monocytes and differentiated macrophages. Phytomedicine 2010; 17:1106-1113. [PMID: 20570123 DOI: 10.1016/j.phymed.2010.03.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 02/26/2010] [Accepted: 03/31/2010] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Willow bark extract is frequently used in the treatment of painful rheumatological diseases, such as arthritis and back pain. Its effect has been attributed to its main component salicin, but pharmacological studies have shown that the clinical efficacy of the willow bark extract cannot be explained by its salicin content alone. Therefore different modes of action have been suggested for the anti-inflammatory effect of willow bark extract. Here, we report in vitro data revelling the effect and mode of action of the aqueous willow bark extract STW 33-I as well as a water-soluble fraction (fraction E [Fr E]) in comparison with well-known non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin (ASA) and diclofenac (Diclo) on pro-inflammatorily activated human monocytes and differentiated macrophages. RESULTS STW 33-I and the water-soluble Fr E showed concentration-dependent and significant anti-inflammatory effects in lipopolysaccharide-activated monocytes. Both inhibited the intracellular protein expression of tumour necrosis factor-alpha (TNFα) as well as the mRNA expression of TNFα and cyclooxygenase 2 (COX-2), and the release of nitric oxide (NO). In addition, apoptosis of pro-inflammatorily activated monocytes was induced. Furthermore, treatment of activated macrophages with STW 33-I inhibited the nuclear translocation of the p65 subunit of the nuclear transcription factor-kappa B (NF-κB p65). CONCLUSIONS The present in vitro investigations suggest a significant anti-inflammatory activity of willow bark water extract STW 33-1 and of its water-soluble fraction by inhibiting pro-inflammatory cytokines (TNFα), COX-2 and nuclear translocation of the transcription factor NF-κB in pro-inflammatorily activated monocytes. Our results provide further evidence for the therapeutic use of STW 33-I in inflammation-related disorders.
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Affiliation(s)
- G A Bonaterra
- Anatomy and Cell Biology, Department of Medical Cell Biology, University of Marburg, Robert-Koch-Str. 8, 35032 Marburg, Germany.
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Shen J, Zhu T, Plastaras J, BarAd V, Metz J, Both S. SU-GG-T-218: A Feasibility Study of Using Convolution Method of a Motion Kernel to Correct Tumor Motion Effect When Treating Pancreatic Cancer with Intensity Modulated Radiation Therapy (IMRT). Med Phys 2010. [DOI: 10.1118/1.3468608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Wainman A, Buster DW, Duncan T, Metz J, Ma A, Sharp D, Wakefield JG. A new Augmin subunit, Msd1, demonstrates the importance of mitotic spindle-templated microtubule nucleation in the absence of functioning centrosomes. Genes Dev 2009; 23:1876-81. [PMID: 19684111 DOI: 10.1101/gad.532209] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The Drosophila Augmin complex localizes gamma-tubulin to the microtubules of the mitotic spindle, regulating the density of spindle microtubules in tissue culture cells. Here, we identify the microtubule-associated protein Msd1 as a new component of the Augmin complex and demonstrate directly that it is required for nucleation of microtubules from within the mitotic spindle. Although Msd1 is necessary for embryonic syncytial mitoses, flies possessing a mutation in msd1 are viable. Importantly, however, in the absence of centrosomes, microtubule nucleation from within the spindle becomes essential. Thus, the Augmin complex has a crucial role in the development of the fly.
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Affiliation(s)
- Alan Wainman
- Department of Zoology, University of Oxford, Oxford, United Kingdom
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Kassaee A, Lin L, Garver E, Metz J, Vapiwala N. SU-FF-T-348: Beam Attenuation and Beam Spoiling Properties of An Electromagnetic Array Used for Patient Localization and Tumor Tracking. Med Phys 2009. [DOI: 10.1118/1.3181829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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50
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Kassaee A, Lin L, Ingram M, Bieda M, Vapiwala N, Metz J. SU-FF-T-473: Time Response Study of Calypso Localization and Tracking System for Moving Tumors. Med Phys 2009. [DOI: 10.1118/1.3181960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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